Fish provides more health benefits than supplements

Eating fish high in omega-3 fatty acids slightly reduces the risk for stroke, a large review of studies has found, but taking supplements of omega-3 fatty acids does not have the same effect.

Researchers writing in the online journal BMJ reviewed data from 38 studies that included almost 800,000 subjects and 34,817 cerebrovascular incidents. The studies varied in size and methodology; some were based on self-reporting of diets, some on blood tests, some on supplements. The researchers reviewed studies of healthy people and of those who had cerebrovascular disease.

The data showed that eating two to four servings of fish a week reduced stroke risk by 6 percent compared with eating one serving or less, and having five servings a week reduced the risk by 12 percent. But the results of the randomized trials that had used omega-3 supplements showed no significant effect on risk.

“We think any beneficial effect of omega-3s is quite small,” said the lead author, Dr. Rajiv Chowdhury, an epidemiologist at the University of Cambridge, “whereas fish comes with a package of many good nutrients and only small amounts of saturated fat.”

What you do not eat when you eat fish may be just as important, Chowdhury said.